[35.07] Deneb: Five Years of H Alpha Monitoring

Ritter Observatory's archive of spectra of Deneb covers the
period 1993 through the present. In an initial survey of the
archival data, we studied the H alpha region of 339 spectra
taken during the 1997-2001 observing seasons with the
1-meter telescope and its fiber-fed spectrograph, which has
a spectral resolving power of 26,000. The present results
are based on inspection of dynamical spectra constructed
with IRAF and SAOImage DS9. Telluric absorption lines have
been removed. The H alpha profile has a P Cygni morphology,
with an emission component that is highly variable in
strength. Superimposed on blue wing of the absorption
component, there is almost always a secondary absorption
feature at a radial velocity of about -100 km s-1.
Sometimes the feature progresses to more negative
velocities, as do DACs in P Cygni wind lines in hotter
stars, but sometimes the feature remains stationary. In
1997, it exhibited cyclical behavior, with ``absorption
events'' occurring approximately every 40 days. There is
subtle evidence of similar behavior in 2000, but in the
other years, the waxing and waning of the feature appear to
be largely stochastic.

Research at Ritter Observatory is supported by The
University of Toledo, the Fund for Astrophysical Research,
and the American Astronomical Society Small Grants Program
(NASA funds). Community access to the facility is supported
by NSF-PREST. Allgaier's participation was supported by the
NSF-REU program.